The only thing from the interview I care about: "We are thinking about how to make Android handle updates better. We see ways we can do this. It's early days. We're talking with our partners and working our way through it. We need time to figure out the mechanics, but it's definitely an area of focus for me and for the team." We've seen empty promises about this before, though.

I 'll enter grumpy mode again, but doesn't the unstable ABI of the Linux kernel prevent any attempt at providing smooth Android upgrades?

From a practical perspective, non-open drivers made for a certain Linux kernel version are useless for subsequent versions. And those *bleep*ing SoC manufacturers won't put their drivers in the tree (aka open them up). So, drivers must be rewritten every time a new Android version (with a new Linux kernel version) is released.

Ever wondered why even Google gives up on upgrading their Nexus phones after some versions? Or why the Nexus S had stability issues when it initially got the upgrade to ICS? (hint: driver issues).

In a parallel universe where SoC manufacturers have their drivers in the tree, you are correct. Would be nice if SoC manufacturers opened their drivers, but they don't want to do it.
If a driver is not in the source tree, it's probably useless for subsequent versions of the Linux kernel. Isn't this right?

But in any case, there have been many articles pointing out that most of the delay in the states is due to carrier certification of each update, rather than code modifications and incompatibilities with the new Android update from google.

Then why unbranded (not carrier locked) Nexus S devices took months to receive ICS? Shouldn't ICS have been served a week after it appeared on the Galaxy Nexus? Hint: Driver issues.

They give up on upgrading their phones after some versions? I could be wrong, but isn't the Nexus One the only Nexus device not running the latest version of Android? And wasn't that due to the old hardware (small amount of internal storage, slow GPU)?